I tried this product to see if it was worth something, but it had absolutely no effects on my. A little bit of research shows that if you're after protein, meat, fish, eggs or milk are a better source. If you are lactose intolerant and/or vegetarian, maybe some whey protein would do better for you. As for vitamin B12, I prefer to take it with a multivitamin supplement.
The suggested intake amount for this spirulina tablets is pretty inconvenient (6 tablets daily) and they smell like fish food.
I'm NOT buying it again.